Rice hybrid RH101

ABSTRACT

A novel rice hybrid, designated RH101, is disclosed. The invention relates to the seeds of rice hybrid RH101, to the plants of rice RH101 and to methods for producing a rice plant produced by crossing the parent known as P1015 with the sterile line designated as S0505. The invention further relates to hybrid rice seeds and plants produced by crossing the hybrid RH101 with another rice cultivar.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a new and distinctive ricehybrid, designated RH101. Rice is an ancient agricultural crop and istoday one of the principal food crops of the world. There are twocultivated species of rice: Oryza sativa L., the Asian rice, and O.glaberrima Steud., the African rice. O. sativa L. constitutes virtuallyall of the world's cultivated rice and is the species grown in theUnited States. Three major rice producing regions exist in the UnitedStates: the Mississippi Delta (Arkansas, Mississippi, northeastLouisiana, southeast Missouri), the Gulf Coast (southwest Louisiana,southeast Texas), and the Central Valleys of California.

[0002] Rice is a semi aquatic crop that benefits from flooded soilconditions during part or all of the growing season. In the UnitedStates, rice is grown on flooded soils to optimize grain yields. Heavyclay soils or silt loam soils with hard pan layers about 30 cm below thesurface are typical rice-producing soils because they minimize waterlosses from soil percolation. Rice production in the United States canbe broadly categorized as either dry-seeded or water-seeded. In thedry-seeded system, rice is sown into a well-prepared seed bed with agrain drill or by broadcasting the seed and incorporating it with a diskor harrow. Moisture for seed germination is from irrigation or rainfall.Another method of planting by the dry-seeded system is to broadcast theseed by airplane into a flooded field, then promptly drain the waterfrom the field. For the dry-seeded system, when the plants have reachedsufficient size (four- to five-leaf stage), a shallow permanent flood ofwater 5 to 16 cm deep is applied to the field for the remainder of thecrop season.

[0003] In the water-seeded system, rice seed is soaked for 12 to 36hours to initiate germination, and the seed is broadcast by airplaneinto a flooded field. The seedlings emerge through a shallow flood, orthe water may be drained from the field for a short period of time toenhance seedling establishment. A shallow flood is maintained until therice approaches maturity. For both the dry-seeded and water-seededproduction systems, the fields are drained when the crop is mature, andthe rice is harvested 2 to 3 weeks later with large combines. In ricebreeding programs, breeders try to employ the production systemspredominant in their respective region. Thus, a drill-seeded breedingnursery is used by breeders in a region where rice is drill-seeded and awater-seeded nursery is used in regions where water-seeding isimportant.

[0004] Rice in the United States is classified into three primary markettypes by grain size, shape, and chemical composition of the endosperm:long-grain, medium grain and short-grain. Typical U.S. long-grainhybrids cook dry and fluffy when steamed or boiled, whereas medium- andshort-grain hybrids cook moist and sticky. Long-grain cultivars havebeen traditionally grown in the southern states and generally receivehigher market prices.

[0005] Rice plants (Oryza sativa) naturally self-pollinate and haveperfect flowers, that are they have both male and female structureswithin the same flower. Rice plants, left to themselves, willself-pollinate and will therefore be substantially homozygous at mostgene loci.

[0006] Although specific breeding objectives vary somewhat in thedifferent regions, increasing yield is a primary objective in allprograms. Grain yield of rice is determined by the number of paniclesper unit area, the number of fertile florets per panicle, and grainweight per floret. Increases in any or all of these yield components mayprovide a mechanism to obtain higher yields. Heritable variation existsfor all of these components, and breeders may directly or indirectlyselect for increases in any of them.

[0007] There are numerous steps in the development of any novel,desirable plant germplasm. Plant breeding begins with the analysis anddefinition of problems and weaknesses of the current germplasm, theestablishment of program goals, and the definition of specific breedingobjectives. The next step is selection of germplasm that possess thetraits to meet the program goals. The goal is to combine in a singlevariety an improved combination of desirable traits from the parentalgermplasm. These important traits may include higher seed yield,resistance to diseases and insects, better stems and roots, tolerance tolow temperatures, and better agronomic characteristics on grain quality.

[0008] Choice of breeding or selection methods depends on the mode ofplant reproduction, the heritability of the trait(s) being improved, andthe type of cultivar used commercially (e.g., F₁ hybrid cultivar,pureline cultivar, etc.). For highly heritable traits, a choice ofsuperior individual plants evaluated at a single location will beeffective, whereas for traits with low heritability, selection should bebased on mean values obtained from replicated evaluations of families ofrelated plants. Popular selection methods commonly include pedigreeselection, modified pedigree selection, mass selection, and recurrentselection, or a combination of these methods.

[0009] The complexity of inheritance influences choice of the breedingmethod. Backcross breeding is used to transfer one or a few favorablegenes for a highly heritable trait into a desirable cultivar. Thisapproach has been used extensively for breeding disease-resistantcultivars. Various recurrent selection techniques are used to improvequantitatively inherited traits controlled by numerous genes. The use ofrecurrent selection in self-pollinating crops depends on the ease ofpollination, the frequency of successful hybrids from each pollination,and the number of hybrid offspring from each successful cross.

[0010] Each breeding program should include a periodic, objectiveevaluation of the efficiency of the breeding procedure. Evaluationcriteria vary depending on the goal and objectives, but should includegain from selection per year based on comparisons to an appropriatestandard, overall value of the advanced breeding lines, and number ofsuccessful cultivars produced per unit of input (e.g., per year, perdollar expended, etc.).

[0011] Promising advanced breeding lines are thoroughly tested andcompared to appropriate standards in environments representative of thecommercial target area(s) for three or more years. The best lines arecandidates for new commercial cultivars and hybrids; those stilldeficient in a few traits may be used as parents to produce newpopulations for further selection.

[0012] These processes, which lead to the final step of marketing anddistribution, usually take from eight to 12 years from the time thefirst cross is made and may rely on the development of improved breedinglines as precursors. Therefore, development of new cultivars and hybridsis a time-consuming process that requires precise forward planning,efficient use of resources, and a minimum of changes in direction.

[0013] Once a single plant is homozygous at all or nearly all loci, arice variety can be produced from this single plant through simplegenerational advance, as long as external pollen flow is controlled andany apparent off-types in the population are removed. Developing sterileand pollinator lines for rice hybrids requires additional steps beyonddeveloping varieties. The hybridizing system used in this invention isreferred to as the 2-line system, because only 2 parental lines arerequired.

[0014] The development of hybrid parents, while a part of the selectionprocess from the initiation of the breeding cross, nonetheless requiresmore steps, and more time. Not only do the lines have to be developedand purified (as described above), but then hybrid seed must beproduced, and all possible hybrid combinations must be tested to findthe best combination.

[0015] In developing hybrid rice lines, it is essential to utilizeparent lines which, when combined, will give optimal quality and yieldcharacteristics. Also, both parents must have seed productionperformance which will result in an economically viable hybrid. Mostimportantly, rice hybrids must fit farmers' production systems withoutrequiring extensive operational changes.

[0016] A most difficult task is the identification of individuals thatare genetically superior, because for most traits the true genotypicvalue is masked by other confounding plant traits or environmentalfactors. One method of identifying a superior plant is to observe itsperformance relative to other experimental plants and to a widely grownstandard hybrid. If a single observation is inconclusive, replicatedobservations provide a better estimate of its genetic worth.

[0017] The goal of plant breeding is to develop new, unique and superiorrice cultivars and hybrids. The breeder initially selects and crossestwo or more parental lines, followed by self-pollination and selection,producing many new genetic combinations. The breeder can theoreticallygenerate billions of different genetic combinations via crossing,selfing and mutations. The breeder has no direct control at the cellularlevel. Therefore, two breeders will never develop the same line, or evenvery similar lines, having the same rice traits.

[0018] Each year, the plant breeder selects the germplasm to advance tothe next generation. This germplasm is grown under unique and differentgeographical, climatic and soil conditions, and further selections arethen made, during and at the end of the growing season. The cultivarsand hybrids which are developed are unpredictable. This unpredictabilityis because the breeder's selection occurs in unique environments, withno control at the DNA level (using conventional breeding procedures),and with millions of different possible genetic combinations beinggenerated. A breeder of ordinary skill in the art cannot predict thefinal resulting lines he develops, except possibly in a very gross andgeneral fashion. The same breeder cannot produce the same cultivar twiceby using the exact same original parents and the same selectiontechniques. This unpredictability results in the expenditure of largeamounts of research monies to develop superior new rice parents orhybrids.

[0019] The development of new rice parent lines involves the selectionof parental lines which collectively contain all required genotypictraits. Crosses (one or several) will be required, and the progeny fromthese crosses will be the starting point for further development.

[0020] Pedigree breeding and recurrent selection breeding methods areused to develop parent lines from breeding populations. Breedingprograms combine desirable traits from two or more cultivars or variousbroad-based sources into breeding pools from which parent lines aredeveloped by selfing and selection of desired phenotypes. The new parentlines are used to produce experimental hybrids, which are evaluated todetermine which have commercial potential.

[0021] Pedigree breeding is used commonly for the improvement ofself-pollinating crops. Two parents which possess favorable,complementary traits are crossed to produce an F₁. An F₂ population isproduced by selfing one or several F₁'s. Selection of the bestindividuals may begin in the F₂ population; then, beginning in the F₃,the best individuals in the best families are selected. Replicatedtesting of families can begin in the F₄ generation to improve theeffectiveness of selection for traits with low heritability. At anadvanced stage of inbreeding (i.e., F₆ and F₇), the best lines, hybridsor mixtures of phenotypically similar lines are tested for potentialrelease as new parent lines or hybrids.

[0022] Mass and recurrent selections can be used to improve populationsof either self- or cross-pollinating crops. A genetically variablepopulation of heterozygous individuals is either identified or createdby intercrossing several different parents. The best plants are selectedbased on individual superiority, outstanding progeny, or excellentcombining ability. The selected plants are intercrossed to produce a newpopulation in which further cycles of selection are continued.

[0023] Backcross breeding has been used to transfer genes for a simplyinherited, highly heritable trait into a desirable homozygous cultivaror inbred line which is the recurrent parent. The source of the trait tobe transferred is called the donor parent. The resulting plant isexpected to have the attributes of the recurrent parent (e.g., cultivar)and the desirable trait transferred from the donor parent. After theinitial cross, individuals possessing the phenotype of the donor parentare selected and repeatedly crossed (backcrossed) to the recurrentparent. The resulting plant is expected to have the attributes of therecurrent parent (e.g., cultivar) and the desirable trait transferredfrom the donor parent.

[0024] The single-seed descent procedure in the strict sense refers toplanting a segregating population, harvesting a sample of one seed perplant, and using the one-seed sample to plant the next generation. Whenthe population has been advanced from the F₂ to the desired level ofinbreeding, the plants from which lines are derived will each trace todifferent F₂ individuals. The number of plants in a population declineseach generation due to failure of some seeds to germinate or some plantsto produce at least one seed. As a result, not all of the F₂ plantsoriginally sampled in the population will be represented by a progenywhen generation advance is completed.

[0025] In a multiple-seed procedure, rice breeders commonly harvest oneor more seeds from each plant in a population and thresh them togetherto form a bulk. Part of the bulk is used to plant the next generationand part is put in reserve. The procedure has been referred to asmodified single-seed descent or the pod-bulk technique.

[0026] The multiple-seed procedure has been used to save labor atharvest. It is considerably faster to thresh panicles with a machinethan to remove one seed from each by hand for the single-seed procedure.The multiple-seed procedure also makes it possible to plant the samenumber of seeds of a population each generation of inbreeding. Enoughseeds are harvested to make up for those plants that did not germinateor produce seed.

[0027] Descriptions of other breeding methods that are commonly used fordifferent traits and crops can be found in one of several referencebooks (e.g., Allard, 1960; Simmonds, 1979; Sneep et al., 1979; Fehr,1987).

[0028] Proper testing should detect any major faults and establish thelevel of superiority or improvement over current cultivars and hybrids.In addition to showing superior performance, there must be a demand fora new cultivar or hybrid that is compatible with industry standards orwhich creates a new market. The introduction of a new hybrid will incuradditional costs to the seed producer, the grower, processor andconsumer; for special advertising and marketing, altered seed andcommercial production practices, and new product utilization. Thetesting preceding release of a new hybrid should take into considerationresearch and development costs as well as technical superiority of thefinal hybrid. For seed-propagated hybrids, it must be feasible toproduce seed easily and economically.

[0029] Rice, Oryza sativa L., is an important and valuable field crop.Thus, a continuing goal of plant breeders is to develop stable, highyielding rice cultivars and hybrids that are agronomically sound. Thereasons for this goal are obviously to maximize the amount of grainproduced on the land used and to supply food for both animals andhumans. To accomplish this goal, the rice breeder must select anddevelop rice plants that have the traits that result in superiorcultivars and hybrids.

SUMMARY OF THE INVENTION

[0030] According to the invention, there is provided a novel ricehybrid, designated RH101. This invention thus relates to the seeds ofrice hybrid RH101, to the plants of rice hybrid RH101 and to methods forproducing a rice hybrid by crossing the parent lines of rice hybridRH101.

[0031] The invention also relates to methods of producing hybrid riceplants by crossing inbred rice line P1015 as a pollen donor, withmale-sterile rice S-Lines to restore fertility in the F₁ hybrid plants.Further, the invention relates to hybrid rice plants and seeds in whichinbred rice line S0505 is the female parent.

[0032] Thus, any such methods using the rice variety RH101 are part ofthis invention: selfing, backcrosses, hybrid production, crosses topopulations, and the like. All plants produced using rice variety RH101as a parent are within the scope of this invention.

[0033] In another aspect, the present invention provides for hybridRH101 where either parent or both parents are single gene convertedparent lines of RH101. The single transferred gene may preferably be adominant or recessive allele. Preferably, the single transferred genewill confer such traits as herbicide resistance, insect resistance,resistance for bacterial, fungal, or viral disease, male fertility, malesterility, enhanced nutritional quality, and industrial usage. Thesingle gene may be a naturally occurring rice gene or a transgeneintroduced through genetic engineering techniques.

[0034] In another aspect, the present invention provides regenerablecells for use in tissue culture of rice plant RH101. Preferably, theregenerable cells in such tissue cultures will be embryos, protoplasts,meristematic cells, callus, pollen, leaves, anthers, root tips, flowers,seeds, panicles or stems. Still further, the present invention providesrice plants regenerated from the tissue cultures of the invention.

Definitions

[0035] In the description and tables which follow, a number of terms areused. In order to provide a clear and consistent understanding of thespecification and claims, including the scope to be given such terms,the following definitions are provided:

[0036] Days to 50% heading. Average number of days from seeding to theday when 50% of all panicles are exerted at least partially through theleaf sheath. A measure of maturity.

[0037] Grain Yield. Grain yield is measured in pounds per acre and at14.0% moisture. Grain yield of rice is determined by the number ofpanicles per unit area, the number of fertile florets per panicle, andgrain weight per floret.

[0038] Lodging Percent. Lodging is measured as a subjective rating andis percentage of the plant stems leaning or fallen completely to theground before harvest.

[0039] Grain Length (L). Length of a rice grain is measured inmillimeters.

[0040] Grain Width (W). Width of a rice grain is measured inmillimeters.

[0041] Length/Width (L/W) Ratio. This ratio is determined by dividingthe average length (L) by the average width (W).

[0042] 1000 Grain Wt. The weight of 1000 rice grains as measured ingrams.

[0043] Harvest Moisture. The percent of moisture of the grain whenharvested.

[0044] Plant Height. Plant height in centimeters is taken from soilsurface to the tip of the extended panicle at harvest.

[0045] Total Milling. Total milled rice as a percent of rough rice.

[0046] Protein. Percent of protein in the milled grain.

[0047] Breakdown. The peak viscosity minus the hot paste viscosity.

[0048] Apparent Amylose Percent. The most important grain characteristicthat describes cooking behavior in each grain class, or type, i.e.,long, medium and short grain. The percentage of the endosperm starch ofmilled rice that is amylose. Standard long grains contain 20 to 23%amylose. Rexmont type long grains contain 24 to 25% amylose. Short andmedium grains contain 16 to 19% amylose. Waxy rice contains 0% amylose.Amylose values will vary over environments.

[0049] S0505: Line Pei Ai 64s

[0050] P1015: Line Lemont

[0051] Alkali Spreading Value. Indicator of gelatinization temperatureand an index that measures the extent of disintegration of milled ricekernel in contact with dilute alkali solution. Standard long grains have3 to 5 Alkali Spreading Value (intermediate gelatinization temperature).

[0052] RVA Viscosity. Rapid Visco Analyzer is a new and widely usedlaboratory instrument to examine paste viscosity, or thickening abilityof milled rice during the cooking process.

[0053] Hot Paste Viscosity. Viscosity measure of rice flour/water slurryafter being heated to 95 Centigrade. Lower values indicate softer andstickier cooking types of rice.

[0054] Paste Temperature (also called Initial viscosity increasetemperature). The temperature at which a defined flour-water mixtureexhibits a measurable viscosity increase under a standardized,instrument-specific (Rapid Visco Analyser) cooking cycle.

[0055] Paste Time. The time at which a defined flour-water mixtureexhibits a measurable viscosity increase under a standardized,instrument-specific (Rapid Visco Analyser) cooking cycle.

[0056] Final Viscosity. Viscosity achieved at the end of a Rapid ViscoAnalyser cooking cycle.

[0057] Peak Time. The time at which peak (maximum) hot-paste viscosityis attained during a standardized, instrument-specific (Rapid ViscoAnalyser) cooking cycle.

[0058] Trough (also called hot-paste viscosity). The viscosity of adefined flour-water mixture after it has been heated to, and held, atthe maximum temperature of a standardized, instrument-specific (RapidVisco Analyser) cooking cycle.

[0059] Trough time. The time at which the Trough (hot-paste viscosity)occurs when a defined flour-water mixture has been heated to and held atthe maximum temperature of a standardized, instrument-specific (RapidVisco Analyser) cooking cycle.

[0060] Amylose percent (also called apparent amylose). A linear fractionof starch that is correlated with cooking and eating qualities. Theapparent amylose content of milled rice may be classified as waxy (lessthan 2%), low (7-20%), intermediate (20-25%) and high (over 25%).Apparent amylose is normally determined on breeding selections. It isbased on iodine colorimetry at pH 4.5-4.7.

[0061] Alkali Spreading Value (ASV). Number from 1 to 7 indicating thesusceptibility of intact milled rice kernels to alkali disintegration. Alow value is given to rice that does not readily digest in alkali. Thetest is typically used in breeding to screen gelatinization temperatureof rice.

[0062] Starch Index. The sum of apparent amylose value plus alkalispreading value. This value correlates with cooking properties of rice.

[0063] Chalk. An opaque region of the rice kernel due to loose packingof the starch granules. Chalk may occur throughout or in a part of thekernel.

[0064] Whole Milling (also called Head rice milling yield). The quantityof milled head (¾-whole) rice produced in the milling of rough rice to awell-milled degree, usually expressed in the United States as percent ofrough rice by weight.

[0065] Total Milling (also called Milling yield). The quantity of totalmilled rice produced in the milling of rough rice to a well-milleddegree; it is usually expressed as percent of rough rice by weight, butwhen specified, may be expressed as percent of brown rice.

[0066] Cold Paste Viscosity. Viscosity measure of rice flour/waterslurry after being heated to 95° C. and uniformly cooled to 50° C.(American Association of Cereal Chemist). Values less than 200 for coldpaste indicate softer cooking types of rice.

[0067] Consistency. Cold paste viscosity minus hot paste viscosity.

[0068] Gelatinization temperature. The temperature at which a definedflour-water mixture exhibits a measurable viscosity increase under astandardized, instrument-specific, cooking cycle (also known as “initialviscosity increase temperature”).

[0069] Peak temperature, at peak viscosity. The temperature at whichpeak hot paste viscosity is attained.

[0070] Peak viscosity, hot paste. The maximum viscosity attained duringheating when a standardized, instrument-specific protocol is applied toa defined rice flour and water slurry.

[0071] Setback viscosity. Cold paste viscosity minus peak hot pasteviscosity.

[0072] Allele. Allele is any of one or more alternative forms of a gene,all of which alleles relate to one trait or characteristic. In a diploidcell or organism, the two alleles of a given gene occupy correspondingloci on a pair of homologous chromosomes.

[0073] Backcrossing. Backcrossing is a process in which a breederrepeatedly crosses hybrid progeny back to one of the parents (recurrentparent), for example, a first generation hybrid F₁ with one of theparental genotypes of the F₁ hybrid.

[0074] Quantitative Trait Loci (QTL). Quantitative trait loci (QTL)refer to genetic loci that control to some degree numericallyrepresentable traits that are usually continuously distributed.

[0075] Regeneration. Regeneration refers to the development of a plantfrom tissue culture.

[0076] Single Gene Converted. Single gene converted or conversion plantrefers to plants which are developed by a plant breeding techniquecalled backcrossing wherein essentially all of the desired morphologicaland physiological characteristics of an inbred are recovered in additionto the single gene transferred into the variety via the backcrossingtechnique or via genetic engineering.

[0077] Relative Maturity. Days to 50% heading relative to a common checkvariety such as Cypress.

DETAILED DESCRIPTION OF THE INVENTION

[0078] The present invention relates to a hybrid rice, designated, andseeds and plants derived from the hybrid. The invention also relates tohybrid plants and seeds and any further progeny or descendants of thehybrid derived by crossing RH101 as a pollen donor. The invention isalso directed to methods for producing a rice plant by crossing a firstparent rice plant with a second parent rice plant wherein the firstparent rice plant is P1015 and the second parent rice plant is S0505.Rice plant from the RH101 hybrid. Thus, any methods using the hybridrice line RH101 in backcrosses, hybrid production, crosses topopulations, and the like, are part of this invention. All plants whichare a progeny of or descend from hybrid rice line RH101 are within thescope of this invention.

[0079] Rice hybrid RH101 is a high yielding, very early maturing,photoperiod insensitive, long grain male fertile hybrid rice line. It isproduced from the cross of the male fertile line P1015, and the malesterile line S0505. It has been tested against the common varietalchecks Cocodrie, Wells and Cypress in more than 80 replicated trials.The hybrid has shown uniformity and stability, as described in thefollowing hybrid description information. It has been produced andtested a sufficient number of generations with careful attention touniformity of plant type. The hybrid has been increased with continuedobservation for uniformity of the parent lines.

[0080] Rice Hybrid RH101 has the following morphologic and othercharacteristics (based primarily on data collected at Alvin, Tex.).

Variety Description Information

[0081] Maturity

[0082] Days to maturity: 107 days from planting to harvesting

[0083] Maturity Class (50% heading—South): Very Early (70-85 days)

[0084] CULM (Degrees from perpendicular after flowering)

[0085] Angle: Erect (less than 30)

[0086] Length: 120 cm (Soil level to top of extended panicle on mainstem)

[0087] Height Class: tall

[0088] Internode Color (After flowering): Green

[0089] Strength (Lodging resistance): Moderately Strong

[0090] FLAG LEAF (After Flowering)

[0091] Length: 37 cm

[0092] Width: 2.1 cm

[0093] Pubescence: Pubescent

[0094] Leaf Angle (After flowering): horizontal

[0095] Blade Color: Green

[0096] Basal Leaf Sheath Color: Green

[0097] Ligule

[0098] Color (Late vegetative state): White

[0099] Shape: 2-Cleft

[0100] Collar Color (Late vegetative stage): Pale green

[0101] Auricle Color (Late vegetative stage): Pale green

[0102] Panicle

[0103] Length: 27 cm

[0104] Type: Intermediate

[0105] Secondary Branching: Light

[0106] Exsertion (near maturity): 90-99% exserted

[0107] Axis: Droopy

[0108] Shattering: Moderate (1-5%)

[0109] Threshability: Easy

[0110] Grain (Spikelet)

[0111] Awns (After full heading): Absent

[0112] Apiculus Color (At maturity): purple apex

[0113] Stigma Color: Purple

[0114] Stigma exsertion (At flowering): >50%

[0115] Lemma and Palea Color (At maturity): Straw

[0116] Lemma and Palea Pubescence: pubescent

[0117] Spikelet Sterility (At maturity): Highly fertile (>90%)

[0118] Grain (Seed)

[0119] Seed Coat Color: Light brown

[0120] Endosperm Type: Nonglutinous (non-waxy)

[0121] Endosperm Translucency: Intermediate

[0122] Endosperm Chalkiness: Small (less than 10% of sample)

[0123] Scent: Nonscented

[0124] Shape Class: Long Measurements: Length Width L/W 1000 Grains (mm)(mm) Ratio (grams) Milled 6.86 2.16 3.18 19.0

[0125] Milling Yield (% whole kernel (head) rice to rough rice): 46-54%

[0126] Amylose: 23%

[0127] Alkali Spreading value: 3.3 (1.5% KOH Solution)

[0128] Gelatinization temperature type: High

[0129] Resistance to Low Temperature

[0130] Germination and Seedling Vigor:

[0131] Flowering (Spikelet fertility):

[0132] Seedling Vigor not Related to Low Temperature

[0133] Vigor:

[0134] Blast Resistance (Pyricularia oryzae)

[0135] Group/Number: IB-1, 5, 45, 49, 54; IC-1, 17; ID-1, 13; IE-1;IG-1; IH-1.

[0136] Resistance to Other Diseases

[0137] Sheath Blight Rhiuzoctonia solani: 7 (check=Gulfmont=7)

[0138] Straight Head: 3, (check: Cypress=2; Gulfmont=2)

[0139] Kernel Smut Neovossia horrida/Tilletia barclayana: 7(check=Cypress=7)

[0140] Hybrid designated RH101 has shown uniformity and stability withinthe limits of environmental influence for all the traits as describedabove. The parents have been self pollinated a sufficient number ofgenerations with careful attention paid to uniformity of plant type toensure homozygosity and phenotypic stability. The parental lines havebeen increased both by hand and in isolated fields with continuedobservation for uniformity. No variant traits have been observed or areexpected in RH101.

[0141] This invention is also directed to methods for producing a riceplant by crossing a first parent rice plant with a second parent riceplant, wherein the first or second rice plant is the rice plant from thehybrid RH101. Further, both first and second parent rice plants may befrom the hybrid RH101. Therefore, any methods using the hybrid RH101 arepart of this invention: selfing, backcrosses, hybrid breeding, andcrosses to populations. Any plants produced using hybrid RH101 as aparent are within the scope of this invention.

[0142] As used herein, the term “plant” includes plant cells, plantprotoplasts, plant cells of tissue culture from which rice plants can beregenerated, plant calli, plant clumps, and plant cells that are intactin plants or parts of plants, such as pollen, flowers, embryos, ovules,seeds, leaves, stems, anthers and the like. Thus, another aspect of thisinvention is to provide for cells which upon growth and differentiationproduce a hybrid having essentially all of the physiological andmorphological characteristics of RH101.

[0143] Culture for expressing desired structural genes and culturedcells are known in the art. Also as known in the art, rice istransformable and regenerable such that whole plants containing andexpressing desired genes under regulatory control may be obtained.General descriptions of plant expression vectors and reporter genes andtransformation protocols can be found in Gruber, et al., “Vectors forPlant Transformation, in Methods in Plant Molecular Biology &Biotechnology” in Glich, et al., (Eds. pp. 89-119, CRC Press, 1993).Moreover GUS expression vectors and GUS gene cassettes are availablefrom Clone Tech Laboratories, Inc., Palo Alto, Calif. while luciferaseexpression vectors and luciferase gene cassettes are available from ProMega Corp. (Madison, Wis.). General methods of culturing plant tissuesare provided for example by Maki, et al., “Procedures for IntroducingForeign DNA into Plants” in Methods in Plant Molecular Biology &Biotechnology, Glich, et al., (Eds. pp. 67-88 CRC Press, 1993); and byPhillips, et al., “Cell-Tissue Culture and In-Vitro Manipulation” inCorn & Corn Improvement, 3rd Edition; Sprague, et al., (Eds. pp.345-387) American Society of Agronomy Inc., 1988. Methods of introducingexpression vectors into plant tissue include the direct infection orco-cultivation of plant cells with Agrobacterium tumefaciens, Horsch etal., Science, 227:1229 (1985). Descriptions of Agrobacterium vectorssystems and methods for Agrobacterium-mediated gene transfer provided byGruber, et al., supra.

[0144] Useful methods include but are not limited to expression vectorsintroduced into plant tissues using a direct gene transfer method suchas microprojectile-mediated delivery, DNA injection, electroporation andthe like. More preferably expression vectors are introduced into planttissues using the microprojectile media delivery with the biolisticdevice Agrobacterium-medicated transformation. Transformant plantsobtained with the protoplasm of the invention are intended to be withinthe scope of this invention.

[0145] The present invention contemplates a rice plant regenerated froma tissue culture of a variety (e.g., RH101) or hybrid plant of thepresent invention. As is well known in the art, tissue culture of ricecan be used for the in vitro regeneration of a rice plant. Tissueculture of various tissues of rices and regeneration of plants therefromis well known and widely published. For example, reference may be had toChu, Q. R., et al., (1999) “Use of bridging parents with high antherculturability to improve plant regeneration and breeding value in rice”,Rice Biotechnology Quarterly 38:25-26; Chu, Q. R., et al., (1998), “Anovel plant regeneration medium for rice anther culture of Southern U.S.crosses”, Rice Biotechnology Quarterly 35:15-16; Chu, Q. R., et al.,(1997), “A novel basal medium for embryogenic callus induction ofSouthern US crosses”, Rice Biotechnology Quarterly 32:19-20; and Oono,K., “Broadening the Genetic Variability By Tissue Culture Methods”, Jap.J. Breed. 33 (Suppl.2), 306-307, illus. 1983, the disclosures of whichare hereby incorporated herein in their entirety by reference. Thus,another aspect of this invention is to provide cells which upon growthand differentiation produce rice plants having the physiological andmorphological characteristics of variety RH101.

Tables

[0146] The following tables present data on the Yield performance of thehybrid RH101 as compared to Cypress. The traits and characteristics ofrice hybrid plants and grain resulting the hybrid RH101 are comparedwith Cypress, a commonly grown rice variety in the U.S. The data wascollected from multiple locations and repeated trials.

[0147] The results in Table 1 compare yield, plant height, maturity,lodging and milling yields of Cypress versus the hybrid of the presentinvention produced by crossing P1015 with S0505. As shown in Table 1 ofthe present invention, the hybrid RH101 unexpectedly has significantlyhigher yield than Cypress, is significantly taller than Cypress, and hassignificantly lower total milling and whole milling yields. Thefollowing symbols may be shown in the table. “***” indicatessignificance at 1%; “**” indicates significance at 5%, “*” indicatessignificance at 10% and “ns” indicates nonsignificant. TABLE 1 YieldPlant Ht. Days to kg/ha cm Heading Lodging % Total Milling % WholeMilling % Cypress 7243.2 93.8 84.2 0.4 0.6862 0.6197 RH101 8806.5 112.376.3 18.8 0.6836 0.5202 Obs rvations 110 106 114 110 94 94 Difference−1563.3 −18.5 7.9 −18.4 0.0026 0.0995 Probability <.0001*** <.0001***<.0001*** <.0001*** 0.6217^(ns) <.0001***

[0148] The results of Table 2 compare the basic quality characteristicsof RH101 and Cypress. Unexpectedly, RH101 had significantly higheramylose, lower ASV and starch index than Cypress. Also, the grain lengthand width and chalk are significantly greater than Cypress, and the L/Wis significantly lower. TABLE 2 Amylose Starch Length Width Chalk % ASVIndex mm Mm L/W ratio % Cypress 21.9 4.39 27.1 6.63 2.08 3.18 2.47 RH10123.4 3.8 26.3 6.74 2.18 3.08 5 Obs rvations 39 46 39 46 46 46 46Difference −1.5 0.59 0.8 −0.11 −0.1 0.1 −2.53 Probability <.0001***0.0053*** 0.0295** 0.0201** <.0001*** 0.0002*** 0.0954*

[0149] Starch characters are compared in Table 3. Peak, trough, troughtime and breakdown are not different between Cypress and RH101. RH101has a lower peak time, paste time, final viscosity, setback andconsistency, and higher past temperature. TABLE 3 Trough Peak Peak TimTrough Time Paste Temp Paste Tim Fianal Visc Breakdown SetbackConsistency Cypress 351.50 9.04 127.20 13.30 74.30 5.30 263.90 224.30−87.60 136.70 RH101 352.30 8.93 130.10 13.20 74.90 5.50 290.30 222.20−62.00 160.20 Observations 10 10 10 10 10 10 10 10 10 10 Difference−0.80 −0.11 −2.90 0.10 −0.60 −0.20 −26.40 2.10 −25.60 −23.50 Probability0.8688^(ns) 0.0846* 0.6171^(ns) 0.1429^(ns) 0.012** 0.0115** 0.0505*0.6592^(ns) 0.0182** 0.0193**

FURTHER EMBODIMENTS OF THE INVENTION

[0150] This invention also is directed to methods for producing a riceplant by crossing a first parent rice plant with a second parent riceplant wherein either the first or second parent rice plant is a hybridrice plant RH101. Further, both first and second parent rice plants cancome from the hybrid rice RH101. Still further, this invention also isdirected to methods for producing a hybrid rice line RH101-derived riceplant by crossing hybrid rice line RH101 with a second rice plant andgrowing the progeny seed, and repeating the crossing and growing stepswith the hybrid rice line RH101-derived plant from 0 to 7 times. Thus,any such methods using the hybrid rice line RH101 are part of thisinvention: selfing, backcrosses, hybrid production, crosses topopulations, and the like. All plants produced using hybrid rice lineRH101 as a parent are within the scope of this invention, includingplants derived from hybrid rice line RH101.

[0151] It should be understood that the parents of hybrid RH101 can,through routine manipulation of cytoplasmic or other factors, beproduced in a male-sterile form. Such embodiments are also contemplatedwithin the scope of the present claims.

[0152] As used herein, the term plant includes plant cells, plantprotoplasts, plant cell tissue cultures from which rice plants can beregenerated, plant calli, plant clumps and plant cells that are intactin plants or parts of plants, such as embryos, pollen, ovules, flowers,kernels, ears, cobs, leaves, husks, stalks, roots, root tips, anthers,silk and the like.

[0153] Duncan, et al., Planta 165:322-332 (1985) reflects that 97% ofthe plants cultured that produced callus were capable of plantregeneration. Subsequent experiments with both inbreds and hybridsproduced 91% regenerable callus that produced plants. In a further studyin 1988, Songstad, et al., Plant Cell Reports 7:262-265 (1988), reportsseveral media additions that enhance regenerability of callus of twoinbred lines. Other published reports also indicated that“nontraditional” tissues are capable of producing somatic embryogenesisand plant regeneration. K. P. Rao et al., Maize Genetics CooperationNewsletter, 60:64-65 (1986), refers to somatic embryogenesis from glumecallus cultures and B. V. Conger, et al., Plant Cell Reports, 6:345-347(1987) indicates somatic embryogenesis from the tissue cultures of cornleaf segments. Thus, it is clear from the literature that the state ofthe art is such that these methods of obtaining plants are, and were,“conventional” in the sense that they are routinely used and have a veryhigh rate of success.

[0154] Tissue culture of corn is described in European PatentApplication, publication 160,390, incorporated herein by reference. Corntissue culture procedures are also described in Green and Rhodes, “PlantRegeneration in Tissue Culture of Maize,” Maize for Biological Research(Plant Molecular Biology Association, Charlottesville, Va. 367-372,(1982)) and in Duncan et al., “The Production of Callus Capable of PlantRegeneration from Immature Embryos of Numerous Zea Mays Genotypes,” 165Planta 322:332 (1985). Thus, another aspect of this invention is toprovide cells which upon growth and differentiation produce rice plantshaving the physiological and morphological characteristics of hybridrice line RH101.

[0155] The utility of hybrid rice line RH101 also extends to crosseswith other species. Commonly, suitable species will be of the familyGraminaceae, and especially of the genera Zea, Tripsacum, Croix,Schlerachne, Polytoca, Chionachne, and Trilobachne, of the tribeMaydeae. Potentially suitable for crosses with RH101 may be the variousvarieties of grain sorghum, Sorghum bicolor (L.) Moench.

[0156] With the advent of molecular biological techniques that haveallowed the isolation and characterization of genes that encode specificprotein products, scientists in the field of plant biology developed astrong interest in engineering the genome of plants to contain andexpress foreign genes, or additional, or modified versions of native, orendogenous, genes (perhaps driven by different promoters) in order toalter the traits of a plant in a specific manner. Such foreignadditional and/or modified genes are referred to herein collectively as“transgenes”. Over the last fifteen to twenty years several methods forproducing transgenic plants have been developed, and the presentinvention, in particular embodiments, also relates to transformedversions of the claimed hybrid.

[0157] Plant transformation involves the construction of an expressionvector which will function in plant cells. Such a vector comprises DNAcomprising a gene under control of or operatively linked to a regulatoryelement (for example, a promoter). The expression vector may contain oneor more such operably linked gene/regulatory element combinations. Thevector(s) may be in the form of a plasmid, and can be used alone or incombination with other plasmids, to provide transformed rice plants,using transformation methods as described below to incorporatetransgenes into the genetic material of the rice plant(s).

[0158] Expression Vectors for Corn Transformation

[0159] Marker Genes—Expression vectors include at least one geneticmarker, operably linked to a regulatory element (a promoter, forexample) that allows transformed cells containing the marker to beeither recovered by negative selection, i.e., inhibiting growth of cellsthat do not contain the selectable marker gene, or by positiveselection, i.e., screening for the product encoded by the geneticmarker. Many commonly used selectable marker genes for planttransformation are well known in the transformation arts, and include,for example, genes that code for enzymes that metabolically detoxify aselective chemical agent which may be an antibiotic or a herbicide, orgenes that encode an altered target which is insensitive to theinhibitor. A few positive selection methods are also known in the art.

[0160] One commonly used selectable marker gene for plant transformationis the neomycin phosphotransferase II (nptII) gene, isolated fromtransposon Tn5, which when placed under the control of plant regulatorysignals confers resistance to kanamycin. Fraley et al., Proc. Natl.Acad. Sci. U.S.A., 80:4803 (1983). Another commonly used selectablemarker gene is the hygromycin phosphotransferase gene which confersresistance to the antibiotic hygromycin. Vanden Elzen et al., Plant Mol.Biol., 5:299 (1985).

[0161] Additional selectable marker genes of bacterial origin thatconfer resistance to antibiotics include gentamycin acetyl transferase,streptomycin phosphotransferase, aminoglycoside-3′-adenyl transferase,the bleomycin resistance determinant. Hayford et al., Plant Physiol.86:1216 (1988), Jones et al., Mol. Gen. Genet., 210:86 (1987), Svab etal., Plant Mol. Biol. 14:197 (1990< Hille et al., Plant Mol. Biol. 7:171(1986). Other selectable marker genes confer resistance to herbicidessuch as glyphosate, glufosinate or broxynil. Comai et al., Nature317:741-744 (1985), Gordon-Kamm et al., Plant Cell 2:603-618 (1990) andStalker et al., Science 242:419-423 (1988).

[0162] Other selectable marker genes for plant transformation are not ofbacterial origin. These genes include, for example, mouse dihydrofolatereductase, plant 5-enolpyruvylshikimate-3-phosphate synthase and plantacetolactate synthase. Eichholtz et al., Somatic Cell Mol. Genet 13:67(1987), Shah et al., Science 233:478 (1986), Charest et al., Plant CellRep. 8:643 (1990).

[0163] Another class of marker genes for plant transformation requirescreening of presumptively transformed plant cells rather than directgenetic selection of transformed cells for resistance to a toxicsubstance such as an antibiotic. These genes are particularly useful toquantify or visualize the spatial pattern of expression of a gene inspecific tissues and are frequently referred to as reporter genesbecause they can be fused to a gene or gene regulatory sequence for theinvestigation of gene expression. Commonly used genes for screeningpresumptively transformed cells include -glucuronidase (GUS,-galactosidase, luciferase and chloramphenicol, acetyltransferase.Jefferson, R. A., Plant Mol. Biol. Rep. 5:387 (1987), Teeri et al., EMBOJ. 8:343 (1989), Koncz et al., Proc. Natl. Acad. Sci U.S.A. 84:131(1987), DeBlock et al., EMBO J. 3:1681 (1984). Another approach to theidentification of relatively rare transformation events has been use ofa gene that encodes a dominant constitutive regulator of the Zea maysanthocyanin pigmentation pathway. Ludwig et al., Science 247:449 (1990).

[0164] Recently, in vivo methods for visualizing GUS activity that donot require destruction of plant tissue have been made available.Molecular Probes publication 2908, Imagene Green™, p. 1-4 (1993) andNaleway et al., J. Cell Biol. 115:151a (1991). However, these in vivomethods for visualizing GUS activity have not proven useful for recoveryof transformed cells because of low sensitivity, high fluorescentbackgrounds and limitations associated with the use of luciferase genesas selectable markers.

[0165] More recently, a gene encoding Green Fluorescent Protein (GFP)has been utilized as a marker for gene expression in prokaryotic andeukaryotic cells. Chalfie et al., Science 263:802 (1994). GFP andmutants of GFP may be used as screenable markers.

[0166] Promoters—Genes included in expression vectors must be driven bynucleotide sequence comprising a regulatory element, for example, apromoter. Several types of promoters are now well known in thetransformation arts, as are other regulatory elements that can be usedalone or in combination with promoters.

[0167] As used herein, “promoter” includes reference to a region of DNAupstream from the start of transcription and involved in recognition andbinding of RNA polymerase and other proteins to initiate transcription.A “plant promoter” is a promoter capable of initiating transcription inplant cells. Examples of promoters under developmental control includepromoters that preferentially initiate transcription in certain tissues,such as leaves, roots, seeds, fibers, xylem vessels, tracheids, orsclerenchyma. Such promoters are referred to as “tissue-preferred”.Promoters which initiate transcription only in certain tissue arereferred to as “tissue-specific”. A “cell type” specific promoterprimarily drives expression in certain cell types in one or more organs,for example, vascular cells in roots or leaves. An “inducible” promoteris a promoter which is under environmental control. Examples ofenvironmental conditions that may effect transcription by induciblepromoters include anaerobic conditions or the presence of light.Tissue-specific, tissue-preferred, cell type specific, and induciblepromoters constitute the class of “non-constitutive” promoters. A“constitutive” promoter is a promoter which is active under mostenvironmental conditions.

[0168] A. Inducible Promoters

[0169] An inducible promoter is operably linked to a gene for expressionin rice. Optionally, the inducible promoter is operably linked to anucleotide sequence encoding a signal sequence which is operably linkedto a gene for expression in rice. With an inducible promoter the rate oftranscription increases in response to an inducing agent.

[0170] Any inducible promoter can be used in the instant invention. SeeWard et al., Plant Mol. Biol. 22:361-366 (1993). Exemplary induciblepromoters include, but are not limited to, that from the ACEI systemwhich responds to copper (Meft et al., PNAS 90:4567-4571 (1993)); In2gene from maize which responds to benzenesulfonamide herbicide safeners(Hershey et al., Mol. Gen Genetics 227:229-237 (1991) and Gatz et al.,Mol. Gen. Genetics 243:32-38 (1994)) or Tet repressor from Tn10 (Gatz etal., Mol. Gen. Genetics 227:229-237 (1991). A particularly preferredinducible promoter is a promoter that responds to an inducing agent towhich plants do not normally respond. An exemplary inducible promoter isthe inducible promoter from a steroid hormone gene, the transcriptionalactivity of which is induced by a glucocorticosteroid hormone. Schena etal., Proc. Natl. Acad. Sci. U.S.A. 88:0421 (1991).

[0171] B. Constitutive Promoters

[0172] A constitutive promoter is operably linked to a gene forexpression in rice or the constitutive promoter is operably linked to anucleotide sequence encoding a signal sequence which is operably linkedto a gene for expression in rice.

[0173] Many different constitutive promoters can be utilized in theinstant invention. Exemplary constitutive promoters include, but are notlimited to, the promoters from plant viruses such as the 35S promoterfrom CaMV (Odell et al., Nature 313:810-812 (1985) and the promotersfrom such genes as rice actin (McElroy et al., Plant Cell 2:163-171(1990)); ubiquitin (Christensen et al., Plant Mol. Biol. 12:619-632(1989) and Christensen et al., Plant Mol. Biol. 18:675-689 (1992)); pEMU(Last et al., Theor. Appl. Genet. 81:581-588 (1991)); MAS (Velten etal., EMBO J. 3:2723-2730 (1984)) and maize H3 histone (Lepetit et al.,Mol. Gen. Genetics 231:276-285 (1992) and Atanassova et al., PlantJournal 2 (3): 291-300 (1992)).

[0174] The ALS promoter, Xba1/NcoI fragment 5′ to the Brassica napusALS3 structural gene (or a nucleotide sequence similarity to saidXbaI/NcoI fragment), represents a particularly useful constitutivepromoter. See PCT application WO96/30530.

[0175] C. Tissue-specific or Tissue-preferred Promoters

[0176] A tissue-specific promoter is operably linked to a gene forexpression in rice. Optionally, the tissue-specific promoter is operablylinked to a nucleotide sequence encoding a signal sequence which isoperably linked to a gene for expression in rice. Plants transformedwith a gene of interest operably linked to a tissue-specific promoterproduce the protein product of the transgene exclusively, orpreferentially, in a specific tissue.

[0177] Any tissue-specific or tissue-preferred promoter can be utilizedin the instant invention. Exemplary tissue-specific or tissue-preferredpromoters include, but are not limited to, a root-preferred promoter,such as that from the phaseolin gene (Murai et al., Science 23:476-482(1983) and Sengupta-Gopalan et al., Proc. Natl. Acad. Sci. U.S.A.82:3320-3324 (1985)); a leaf-specific and light-induced promoter such asthat from cab or rubisco (Simpson et al., EMBO J. 4(11):2723-2729 (1985)and Timko et al., Nature 318:579-582 (1985)); an anther-specificpromoter such as that from LAT52 (Twell et al., Mol. Gen. Genetics217:240-245 (1989)); a pollen-specific promoter such as that from Zm13(Guerrero et al., Mol. Gen. Genetics 244:161-168 (1993)) or amicrospore-preferred promoter such as that from apg (Twell et al., Sex.Plant Reprod. 6:217-224 (1993).

[0178] Signal Sequences for Targeting Proteins to SubcellularCompartments

[0179] Transport of protein produced by transgenes to a subcellularcompartment such as the chloroplast, vacuole, peroxisome, glyoxysome,cell wall or mitochondroin or for secretion into the apoplast, isaccomplished by means of operably linking the nucleotide sequenceencoding a signal sequence to the 5′ and/or 3′ region of a gene encodingthe protein of interest. Targeting sequences at the 5′ and/or 3′ end ofthe structural gene may determine, during protein synthesis andprocessing, where the encoded protein is ultimately compartmentalized.

[0180] The presence of a signal sequence directs a polypeptide to eitheran intracellular organelle or subcellular compartment or for secretionto the apoplast. Many signal sequences are known in the art. See, forexample Becker et al., Plant Mol. Biol. 20:49 (1992), Close, P. S.,Master's Thesis, Iowa State University (1993), Knox, C., et al.,“Structure and Organization of Two Divergent Alpha-Amylase Genes fromBarley”, Plant Mol. Biol. 9:3-17 (1987), Lerner et al., Plant Physiol.91:124-129 (1989), Fontes et al., Plant Cell 3:483496 (1991), Matsuokaet al., Proc. Natl. Acad. Sci. 88:834 (1991), Gould et al., J. Cell.Biol. 108:1657 (1989), Creissen et al., Plant J. 2:129 (1991), Kalderon,et al., A short amino acid sequence able to specify nuclear location,Cell 39:499-509 (1984), Steifel, et al., Expression of a maize cell wallhydroxyproline-rich glycoprotein gene in early leaf and root vasculardifferentiation, Plant Cell 2:785-793 (1990).

[0181] Foreign Protein Genes and Agronomic Genes

[0182] With transgenic plants according to the present invention, aforeign protein can be produced in commercial quantities. Thus,techniques for the selection and propagation of transformed plants,which are well understood in the art, yield a plurality of transgenicplants which are harvested in a conventional manner, and a foreignprotein then can be extracted from a tissue of interest or from totalbiomass. Protein extraction from plant biomass can be accomplished byknown methods which are discussed, for example, by Heney and Orr, Anal.Biochem. 114:92-6 (1981).

[0183] According to a preferred embodiment, the transgenic plantprovided for commercial production of foreign protein is rice. Inanother preferred embodiment, the biomass of interest is seed. For therelatively small number of transgenic plants that show higher levels ofexpression, a genetic map can be generated, primarily via conventionalRFLP, PCR and SSR analysis, which identifies the approximate chromosomallocation of the integrated DNA molecule. For exemplary methodologies inthis regard, see Glick and Thompson, Methods in Plant Molecular Biologyand Biotechnology CRC Press, Boca Raton 269:284 (1993). Map informationconcerning chromosomal location is useful for proprietary protection ofa subject transgenic plant. If unauthorized propagation is undertakenand crosses made with other germplasm, the map of the integration regioncan be compared to similar maps for suspect plants, to determine if thelatter have a common parentage with the subject plant. Map comparisonswould involve hybridizations, RFLP, PCR, SSR and sequencing, all ofwhich are conventional techniques.

[0184] Likewise, by means of the present invention, agronomic genes canbe expressed in transformed plants. More particularly, plants can begenetically engineered to express various phenotypes of agronomicinterest. Exemplary genes implicated in this regard include, but are notlimited to, those categorized below:

[0185] 1. Genes that Confer Resistance to Pests or Disease and thatEncode:

[0186] A. Plant disease resistance genes. Plant defenses are oftenactivated by specific interaction between the product of a diseaseresistance gene (R) in the plant and the product of a correspondingavirulence (Avr) gene in the pathogen. A plant inbred line can betransformed with cloned resistance gene to engineer plants that areresistant to specific pathogen strains. See, for example Jones et al.,Science 266:789 (1994) (cloning of the tomato Cf-9 gene for resistanceto Cladosporium fulvum); Martin et al., Science 262:1432 (1993) (tomatoPto gene for resistance to Pseudomonas syringae pv. Tomato encodes aprotein kinase); Mindrinos et al., Cell 78:1089 (1994) (Arabidopsis RSP2gene for resistance to Pseudomonas syringae).

[0187] B. A Bacillus thuringiensis protein, a derivative thereof or asynthetic polypeptide modeled thereon. See, for example, Geiser et al.,Gene 48:109 (1986), who disclose the cloning and nucleotide sequence ofa Bt-endotoxin gene. Moreover, DNA molecules encoding-endotoxin genescan be purchased from American Type Culture Collection, Manassas, Va.,for example, under ATCC Accession Nos. 40098, 67136, 31995 and 31998.

[0188] C. A lectin. See, for example, the disclose by Van Damme et al.,Plant Molec. Biol. 24:25 (1994), who disclose the nucleotide sequencesof several Clivia miniata mannose-binding lectin genes.

[0189] D. A vitamin-binding protein such as avidin. See PCT applicationUS93/06487, the contents of which are hereby incorporated by reference.The application teaches the use of avidin and avidin homologues aslarvicides against insect pests.

[0190] E. An enzyme inhibitor, for example, a protease or proteinaseinhibitor or an amylase inhibitor. See, for example, Abe et al., J.Biol. Chem. 262:16793 (1987) (nucleotide sequence of rice cysteineproteinase inhibitor), Huub et al., Plant Molec. Biol. 21:985 (1993)(nucleotide sequence of cDNA encoding tobacco proteinase inhibitor 1),Sumitani et al., Biosci. Biotech. Biochem. 57:1243 (1993) (nucleotidesequence of Streptomyces nitrosporeus-amylase inhibitor).

[0191] F. An insect-specific hormone or pheromone such as an ecdysteroidand juvenile hormone, a variant thereof, a mimetic based thereon, or anantagonist or agonist thereof. See, for example, the disclosure byHammock et al., Nature 344:458 (1990), of baculovirus expression ofcloned juvenile hormone esterase, an inactivator of juvenile hormone.

[0192] G. An insect-specific peptide or neuropeptide which, uponexpression, disrupts the physiology of the affected pest. For example,see the disclosures of Regan, J. Biol. Chem. 269:9 (1994) (expressioncloning yields DNA coding for insect diuretic hormone receptor), andPratt et al., Biochem. Biophys. Res. Comm. 163:1243 (1989) (anallostatin is identified in Diploptera puntata). See also U.S. Pat. No.5,266,317 to Tomalski et al., who disclose genes encodinginsect-specific, paralytic neurotoxins.

[0193] H. An insect-specific venom produced in nature by a snake, awasp, etc. For example, see Pang et al., Gene 116:165 (1992), fordisclosure of heterologous expression in plants of a gene coding for ascorpion insectotoxic peptide.

[0194] I. An enzyme responsible for a hyper accumulation of amonterpene, a sesquiterpene, a steroid, hydroxamic acid, aphenylpropanoid derivative or another non-protein molecule withinsecticidal activity.

[0195] J. An enzyme involved in the modification, including thepost-translational modification, of a biologically active molecule; forexample, a glycolytic enzyme, a proteolytic enzyme, a lipolytic enzyme,a nuclease, a cyclase, a transaminase, an esterase, a hydrolase, aphosphatase, a kinase, a phosphorylase, a polymerase, an elastase, achitinase and a glucanase, whether natural or synthetic. See PCTapplication WO 93/02197 in the name of Scott et al., which discloses thenucleotide sequence of a callase gene. DNA molecules which containchitinase-encoding sequences can be obtained, for example, from the ATCCunder Accession Nos. 39637 and 67152. See also Kramer et al., InsectBiochem. Molec. Biol. 23:691 (1993), who teach the nucleotide sequenceof a cDNA encoding tobacco hookworm chitinase, and Kawalleck et al.,Plant Molec. Biol. 21:673 (1993), who provide the nucleotide sequence ofthe parsley ubi4-2 polyubiquitin gene.

[0196] K. A molecule that stimulates signal transduction. For example,see the disclosure by Botella et al., Plant Molec. Biol. 24:757 (1994),of nucleotide sequences for mung bean calmodulin cDNA clones, and Griesset al., Plant Physiol. 104:1467 (1994), who provide the nucleotidesequence of a maize calmodulin cDNA clone.

[0197] L. A hydrophobic moment peptide. See PCT application WO95/16776(disclosure of peptide derivatives of Tachyplesin which inhibit fungalplant pathogens) and PCT application WO95/18855 (teaches syntheticantimicrobial peptides that confer disease resistance), the respectivecontents of which are hereby incorporated by reference.

[0198] M. A membrane permease, a channel former or a channel blocker.For example, see the disclosure of Jaynes et al., Plant Sci 89:43(1993), of heterologous expression of a cecropin-, lytic peptide analogto render transgenic tobacco plants resistant to Pseudomonassolanacearum.

[0199] N. A viral-invasive protein or a complex toxin derived therefrom.For example, the accumulation of viral coat proteins in transformedplant cells imparts resistance to viral infection and/or diseasedevelopment effected by the virus from which the coat protein gene isderived, as well as by related viruses. See Beachy et al., Ann. rev.Phytopathol. 28:451 (1990). Coat protein-mediated resistance has beenconferred upon transformed plants against alfalfa mosaic virus, cucumbermosaic virus, tobacco streak virus, potato virus X, potato virus Y,tobacco etch virus, tobacco rattle virus and tobacco mosaic virus. Id.

[0200] O. An insect-specific antibody or an immunotoxin derivedtherefrom. Thus, an antibody targeted to a critical metabolic functionin the insect gut would inactivate an affected enzyme, killing theinsect. Cf. Taylor et al., Abstract #497, Seventh Int'l Symposium onMolecular Plant-Microbe Interactions (Edinburgh, Scotland) (1994)(enzymatic inactivation in transgenic tobacco via production ofsingle-chain antibody fragments).

[0201] P. A virus-specific antibody. See, for example, Tavladoraki etal., Nature 366:469 (1993), who show that transgenic plants expressingrecombinant antibody genes are protected from virus attack.

[0202] Q. A developmental-arrestive protein produced in nature by apathogen or a parasite. Thus, fungal endo -1,4-D-polygalacturonasesfacilitate fungal colonization and plant nutrient release bysolubilizing plant cell wall homo- -1,4-D-galacturonase. See Lamb etal., Bio/Technology 10:1436 (1992). The cloning and characterization ofa gene which encodes a bean endopolygalacturonase-inhibiting protein isdescribed by Toubart et al., Plant J. 2:367 (1992).

[0203] R. A development-arrestive protein produced in nature by a plant.For example, Logemann et al., Bioi/Technology 10:305 (1992), have shownthat transgenic plants expressing the barley ribosome-inactivating genehave an increased resistance to fungal disease.

[0204] 2. Genes that Confer Resistance to a Herbicide, for Example:

[0205] A. A herbicide that inhibits the growing point or meristem, suchas an imidazalinone or a sulfonylurea. Exemplary genes in this categorycode for mutant ALS and AHAS enzyme as described, for example, by Lee etal., EMBO J. 7:1241 (1988), and Miki et al., Theor. Appl. Genet 80:449(1990), respectively.

[0206] B. Glyphosate (resistance impaired by mutant5-enolpyruvl-3-phosphikimate synthase (EPSP) and aroA genes,respectively) and other phosphono compounds such as glufosinate(phosphinothricin acetyl transferase, PAT and Streptomyces hygroscopicusphosphinothricin-acetyl transferase, bar, genes), and pyridinoxy orphenoxy propionic acids and cycloshexones (ACCase inhibitor-encodinggenes). See, for example, U.S. Pat. No. 4,940,835 to Shah, et al., whichdiscloses the nucleotide sequence of a form of EPSP which can conferglyphosate resistance. A DNA molecule encoding a mutant aroA gene can beobtained under ATCC accession number 39256, and the nucleotide sequenceof the mutant gene is disclosed in U.S. Pat. No. 4,769,061 to Comai.European patent application No. 0 333 033 to Kumada et al., and U.S.Pat. No. 4,975,374 to Goodman et al., disclose nucleotide sequences ofglutamine synthetase genes which confer resistance to herbicides such asL-phosphinothricin. The nucleotide sequence of aphosphinothricin-acetyl-transferase gene is provided in Europeanapplication No. 0 242 246 to Leemans et al., DeGreef et al.,Bio/Technology 7:61 (1989), describe the production of transgenic plantsthat express chimeric bar genes coding for phosphinothricin acetyltransferase activity. Exemplary of genes conferring resistance tophenoxy propionic acids and cycloshexones, such as sethoxydim andhaloxyfop are the Acc1-S1, Acc1-S2 and Acc1-S3 genes described byMarshall et al., Theor. Appl. Genet. 83:435 (1992).

[0207] C. A herbicide that inhibits photosynthesis, such as a triazine(psbA and gs+ genes) and a benzonitrile (nitrilase gene). Przibilla etal., Plant Cell 3:169 (1991), describe the transformation ofChlamydomonas with plasmids encoding mutant psbA genes. Nucleotidesequences for nitrilase genes are disclosed in U.S. Pat. No. 4,810,648to Stalker, and DNA molecules containing these genes are available underATCC Accession Nos. 53435, 67441, and 67442. Cloning and expression ofDNA coding for a glutathione S-transferase is described by Hayes et al.,Biochem. J. 285:173 (1992).

[0208] 3. Genes That Confer or Contribute to a Value-Added Trait, Suchas:

[0209] A. Modified fatty acid metabolism, for example, by transforming aplant with an antisense gene of stearyl-ACP desaturase to increasestearic acid content of the plant. See Knultzon et al., Proc. Natl.Acad. Sci. U.S.A. 89:2624 (1992).

[0210] B. Decreased Phytate Content

[0211] 1) Introduction of a phytase-encoding gene would enhancebreakdown of phytate, adding more free phosphate to the transformedplant. For example, see Van Hartingsveldt et al., Gene 127:87 (1993),for a disclosure of the nucleotide sequence of an Aspergillus nigerphytase gene.

[0212] 2) A gene could be introduced that reduced phytate content. Inmaize, this, for example, could be accomplished, by cloning and thenreintroducing DNA associated with the single allele which is responsiblefor maize mutants characterized by low levels of phytic acid. See Raboyet al., Maydica 35:383 (1990).

[0213] C. Modified carbohydrate composition effected, for example, bytransforming plants with a gene coding for an enzyme that alters thebranching pattern of starch. See Shiroza et al., J. Bacteol. 170:810(1988) (nucleotide sequence of Streptococcus mutantsfructosyltransferase gene), Steinmetz et al., Mol. Gen. Genet 20:220(1985) (nucleotide sequence of Bacillus subtilis levansucrase gene), Penet al., Bio/Technology 10:292 (1992) (production of transgenic plantsthat express Bacillus licheniformis-amylase), Elliot et al., PlantMolec. Biol. 21:515 (1993) (nucleotide sequences of tomato invertasegenes), Søgaard et al., J. Biol. Chem. 268:22480 (1993) (site-directedmutagenesis of barley-amylase gene), and Fisher et al., Plant Physiol.102:1045 (1993) (maize endosperm starch branching enzyme II).

[0214] Methods for Corn Transformation

[0215] Numerous methods for plant transformation have been developed,including biological and physical, plant transformation protocols. See,for example, Miki et al., “Procedures for Introducing Foreign DNA intoPlants” in Methods in Plant Molecular Biology and Biotechnology, GlickB. R. and Thompson, J. E. Eds. (CRC Press, Inc., Boca Raton, 1993) pages67-88. In addition, expression vectors and in vitro culture methods forplant cell or tissue transformation and regeneration of plants areavailable. See, for example, Gruber et al., “Vectors for PlantTransformation” in Methods in Plant Molecular Biology and Biotechnology,Glick B. R. and Thompson, J. E. Eds. (CRC Press, Inc., Boca Raton, 1993)pages 89-119.

[0216] A. Agrobacterium-Mediated Transformation

[0217] One method for introducing an expression vector into plants isbased on the natural transformation system of Agrobacterium. See, forexample, Horsch et al., Science 227:1229 (1985). A. tumefaciens and A.rhizogenes are plant pathogenic soil bacteria which geneticallytransform plant cells. The Ti and Ri plasmids of A. tumefaciens and A.rhizogenes, respectively, carry genes responsible for genetictransformation of the plant. See, for example, Kado, C. I., Crit. Rev.Plant Sci. 10:1 (1991). Descriptions of Agrobacterium vector systems andmethods for Agrobacterium-mediated gene transfer are provided by Gruberet al., supra, Miki et al., supra, and Moloney et al., Plant CellReports 8:238 (1989). See also, U.S. Pat. No. 5,591,616 issued Jan. 7,1997.

[0218] B. Direct Gene Transfer

[0219] Despite the fact the host range for Agrobacterium-mediatedtransformation is broad, some major cereal crop species and gymnospermshave generally been recalcitrant to this mode of gene transfer, eventhough some success has recently been achieved in rice and corn. Hiei etal., The Plant Journal 6:271-282 (1994) and U.S. Pat. No. 5,591,616issued Jan. 7, 1997. Several methods of plant transformation,collectively referred to as direct gene transfer, have been developed asan alternative to Agrobacterium-mediated transformation.

[0220] A generally applicable method of plant transformation ismicroprojectile-mediated transformation wherein DNA is carried on thesurface of microprojectiles measuring 1 to 4 μm. The expression vectoris introduced into plant tissues with a biolistic device thataccelerates the microprojectiles to speeds of 300 to 600 m/s which issufficient to penetrate plant cell walls and membranes. Sanford et al.,Part. Sci. Technol. 5:27 (1987), Sanford, J. C., Trends Biotech. 6:299(1988), Klein et al., Bio/Technology 6:559-563 (1988), Sanford, J. C.,Physiol Plant 7:206 (1990), Klein et al., Biotechnology 10:268 (1992).In corn, several target tissues can be bombarded with DNA-coatedmicroprojectiles in order to produce transgenic plants, including, forexample, callus (Type I or Type II), immature embryos, and meristematictissue.

[0221] Another method for physical delivery of DNA to plants issonication of target cells. Zhang et al., Bio/Technology 9:996 (1991).Alternatively, liposome or spheroplast fusion have been used tointroduce expression vectors into plants. Deshayes et al., EMBO J.,4:2731 (1985), Christou et al., Proc Natl. Acad. Sci. U.S.A. 84:3962(1987). Direct uptake of DNA into protoplasts using CaCl₂ precipitation,polyvinyl alcohol or poly-L-omithine have also been reported. Hain etal., Mol. Gen. Genet 199:161 (1985) and Draper et al., Plant CellPhysiol. 23:451 (1982). Electroporation of protoplasts and whole cellsand tissues have also been described. Donn et al., In Abstracts of VIIthInternational Congress on Plant Cell and Tissue Culture IAPTC, A2-38, p53 (1990); D'Halluin et al., Plant Cell 4:1495-1505 (1992) and Spenceret al., Plant Mol. Biol. 24:51-61 (1994).

[0222] Following transformation of rice target tissues, expression ofthe above-described selectable marker genes allows for preferentialselection of transformed cells, tissues and/or plants, usingregeneration and selection methods now well known in the art.

[0223] The foregoing methods for transformation would typically be usedfor producing a transgenic inbred line. The transgenic inbred line couldthen be crossed, with another (non-transformed or transformed) inbredline, in order to produce a new transgenic inbred line. Alternatively, agenetic trait which has been engineered into a particular rice lineusing the foregoing transformation techniques could be moved intoanother line using traditional backcrossing techniques that are wellknown in the plant breeding arts. For example, a backcrossing approachcould be used to move an engineered trait from a public, non-eliteinbred line into an elite inbred line, or from an inbred line containinga foreign gene in its genome into an inbred line or lines which do notcontain that gene. As used herein, “crossing” can refer to a simple X byY cross, or the process of backcrossing, depending on the context.

[0224] When the term inbred rice plant is used in the context of thepresent invention, this also includes any single gene conversions ofthat inbred. The term single gene converted plant as used herein refersto those rice plants which are developed by a plant breeding techniquecalled backcrossing wherein essentially all of the desired morphologicaland physiological characteristics of an inbred are recovered in additionto the single gene transferred into the inbred via the backcrossingtechnique. Backcrossing methods can be used with the present inventionto improve or introduce a characteristic into the inbred. The termbackcrossing as used herein refers to the repeated crossing of a hybridprogeny back to one of the parental rice plants for that inbred. Theparental rice plant which contributes the gene for the desiredcharacteristic is termed the nonrecurrent or donor parent. Thisterminology refers to the fact that the nonrecurrent parent is used onetime in the backcross protocol and therefore does not recur. Theparental rice plant to which the gene or genes from the nonrecurrentparent are transferred is known as the recurrent parent as it is usedfor several rounds in the backcrossing protocol (Poehlman & Sleper,1994; Fehr, 1987). In a typical backcross protocol, the original inbredof interest (recurrent parent) is crossed to a second inbred(nonrecurrent parent) that carries the single gene of interest to betransferred. The resulting progeny from this cross are then crossedagain to the recurrent parent and the process is repeated until a riceplant is obtained wherein essentially all of the desired morphologicaland physiological characteristics of the recurrent parent are recoveredin the converted plant, in addition to the single transferred gene fromthe nonrecurrent parent.

[0225] The selection of a suitable recurrent parent is an important stepfor a successful backcrossing procedure. The goal of a backcrossprotocol is to alter or substitute a single trait or characteristic inthe original inbred. To accomplish this, a single gene of the recurrentinbred is modified or substituted with the desired gene from thenonrecurrent parent, while retaining essentially all of the rest of thedesired genetic, and therefore the desired physiological andmorphological, constitution of the original inbred. The choice of theparticular nonrecurrent parent will depend on the purpose of thebackcross, one of the major purposes is to add some commerciallydesirable, agronomically important trait to the plant. The exactbackcrossing protocol will depend on the characteristic or trait beingaltered to determine an appropriate testing protocol. Althoughbackcrossing methods are simplified when the characteristic beingtransferred is a dominant allele, a recessive allele may also betransferred. In this instance it may be necessary to introduce a test ofthe progeny to determine if the desired characteristic has beensuccessfully transferred.

[0226] Many single gene traits have been identified that are notregularly selected for in the development of a new inbred but that canbe improved by backcrossing techniques. Single gene traits may or maynot be transgenic, examples of these traits include but are not limitedto, male sterility, waxy starch, herbicide resistance, resistance forbacterial, fungal, or viral disease, insect resistance, male fertility,enhanced nutritional quality, industrial usage, yield stability andyield enhancement. These genes are generally inherited through thenucleus. Some known exceptions to this are the genes for male sterility,some of which are inherited cytoplasmically, but still act as singlegene traits. Several of these single gene traits are described in U.S.Pat. Nos. 5,777,196; 5,948,957 and 5,969,212, the disclosures of whichare specifically hereby incorporated by reference.

Deposit Information

[0227] A deposit of the rice seed of this invention is maintained byRiceTec, Inc., 1925 FM 2917, Alvin, Tex. 77511. Access to this depositwill be available during the pendency of this application to personsdetermined by the Commissioner of Patents and Trademarks to be entitledthereto under 37 CFR 1.14 and 35 USC 122. Upon allowance of any claimsin this application, all restrictions on the availability to the publicof the variety will be irrevocably removed by affording access to adeposit of at least 2,500 seeds of the same variety with the AmericanType Culture Collection, Manassas, Va.

[0228] Although the foregoing invention has been described in somedetail by way of illustration and example for purposes of clarity andunderstanding, it will be obvious that certain changes and modificationsmay be practiced within the scope of the invention, as limited only bythe scope of the appended claims.

What is claimed is:
 1. A rice seed designated RH101, wherein arepresentative sample of said seed has been deposited under ATCCAccession No. ______.
 2. A rice plant, or parts thereof, produced bygrowing the seed of claim
 1. 3. Pollen of the plant of claim
 2. 4. Anovule of the plant of claim
 2. 5. A rice plant, or parts thereof, havingall of the physiological and morphological characteristics of the riceplant of claim
 2. 6. Tissue culture of regenerable cells from the riceplant of claim
 2. 7. The tissue culture of claim 6 wherein the cells orprotoplasts of the tissue culture being from a tissue selected from thegroup consisting of embryos, meristematic cells, pollen, leaves,anthers, roots, root tips, flowers, seeds, and stems.
 8. A rice plantregenerated from the tissue culture of claim
 7. 9. A method forproducing a rice seed comprising crossing a first parent rice plant witha second parent rice plant and harvesting the resultant hybrid riceseed, wherein said first or second parent rice plant is the rice plantof claim
 2. 10. A hybrid rice seed produced by the method of claim 9.11. A hybrid rice plant, or parts thereof, produced by growing saidhybrid rice seed of claim
 10. 12. Rice seed produced from said hybridrice plant of claim
 11. 13. The rice plant, or parts thereof, producedfrom the rice seed of claim
 12. 14. The rice plant of claim 5, furthercomprising a single gene conversion.
 15. The single gene conversion riceplant of claim 14, wherein the gene is introduced by transgenic means.16. The single gene conversion rice plant of claim 14, wherein the geneis a dominant allele.
 17. The single gene conversion rice plant of claim14, wherein the gene is a recessive allele.
 18. The single geneconversion rice plant of claim 14, wherein the gene confers herbicideresistance.
 19. The single gene conversion rice plant of claim 14,wherein the gene confers insect resistance.
 20. The single geneconversion rice plant of claim 14, wherein the gene confers resistanceto bacterial, fungal or viral disease.
 21. The single gene conversionrice plant of claim 14, wherein the gene confers male sterility.
 22. Therice plant, or parts thereof, of claim 2, wherein the plant or partsthereof have been transformed so that its genetic material contains atransgene operably linked to a regulatory element.